HL Leopard 2 - Tank Overhaul

[CaptainNemo12]

Does the BGC 2.0 accept external inputs from the transmitter or is it simply a closed-loop system? In other words, is it possible to "interrupt" the stabilization so that the user can rotate the turret and raise the gun using the sticks on the transmitter?

[wibblywobbly]

Exceptional work, I have only seen brushed motors used once before. He used flywheels to give a momentum effect on braking and acceleration, but the electronics will do that on yours.

Elmod have Leopard 2 sounds in their library. If they are not on your system, you can download them from Elmod.

https://ssl-id.de/www.elmod.eu/sounds.p ... u3msbles20

[ALPHA]

Alpha, a CNC machine is basically a fully automated robot that utilises multiple milling heads to turn out a specific programmed design.

They are amazing bits of kit.

Brilliant work thus far vanhassen.

Yup that's why I said "it was even better" because it's faster and doesn't heat the metal

ALPHA

[Dietrich]

Stunning work there !
Please can I just ask 'Why you used a worm gear ?'..is it simply that it is a very compact drive compared to the more normal 'cluster' of gears ?

[vanhasen]

Does the BGC 2.0 accept external inputs from the transmitter or is it simply a closed-loop system? In other words, is it possible to "interrupt" the stabilization so that the user can rotate the turret and raise the gun using the sticks on the transmitter?

Of course yes. And it works perfectly - when I use RC transmitter turret turns and when I stop it "remembers" the direction I am looking at and maintains it.
Software also allows precise regulation of rotation speed.

Stunning work there !
Please can I just ask 'Why you used a worm gear ?'..is it simply that it is a very compact drive compared to the more normal 'cluster' of gears ?

Hm - its mostly the way to overcome lacks of my skill and woskshop. I already built a standard three-stage gearobox, but I am not 100% satisfied with the result.

And regarding difference between laser and router - both are in fact cnc machines, just with different cutting method/tool. I prefer mill because it is more flexible. Laser can cut or not cut There is no option to make slots, use different shapes of bits etc.

[CaptainNemo12]

Very interesting, could you show us more pictures of how you mounted the brushless motor to the turret base for the turret rotation? Also, is your BGC controller 2-axis or 3-axis? Is it possible to use a 2-axis controller and flip the IMU so that the roll now becomes the yaw?

[vanhasen]

In my model the rotation motor is holding the entire turret - it is the turret base. I used quite a big one, with hole in the shaft which allows me to use a slip ring. Look at the photos - motor is held by an aluminium basket (on the photo its not finished - missing some holes), which is attached to the deck.





Regarding the gimbal controller - the setup is quite simple if you correctly set up roll and yaw axis and motors at the begining. I think that IMU irientation is not important - you can install it however you want, then calibrate it.
I use the most simple 2-axis controller and it is absolutely enough

In the meanwhile I prepared a set of brass mudguards and started working on the Heng Long plastic upper deck.

[CaptainNemo12]

Thank you very much sir! I had doubts about using a BGC for gun stabilization but now you've shown that it is entirely possible! Bravo!

Regarding the gun elevation, is the brushless motor simply connected to the gun swivel via a linkage setup? When the tank is not powered on, does the gun barrel depress due to the weight or have you also installed some sort of gear train as well?

[vanhasen]

Brushless gimbal has to be balanced - you can stabilise a large dslr camera, but each rotation axis has to be exactly in the center of gravity. Which means that without power if you move the camera by hand it remains in last position when you stop.
And in case of gun stabilisation it is a problem... I have a flat turrret floor so there is no space for a simple counterweight. I also wanted to have the same min/max elevation angles as the original tank. So instead of counterweight I had to use another trick.

First I simply attached motor and mantlet with a belt - with gear ratio 1:2. It wasn't enough. First it was not a trinning belt and it was just slipping from time to time. Second - the weight of barrel generates a substantial resistance and I could not set up the controller correctly. Even if i did - the lack of balance cause a controller to work much harder than normally and the effect is motor overheating and large energy consumption.

In second step I added a spring to counter the barrel weight and I replaced the belt mechanism with regular gearbox with a much higher ratio.

[CaptainNemo12]

I see, thanks! I would like to use a hollow shaft gimbal motor to drive my turret as well, since it has an integrated bearing and a slip ring. For a simple direct drive setup without stabilization, do you think a standard 30A RC helicopter ESC will be able to drive a gimbal motor like the one you have?